


Perseverance

by BlissHellfire



Category: Undertale (Video Game)
Genre: Alternate Universe - High School, Cameo: Nightmare/Asgore/Undyne, Gen, Mentioned: Dust/Killer
Language: English
Status: Completed
Published: 2020-02-07
Updated: 2020-02-15
Packaged: 2021-02-26 11:09:18
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 3
Words: 2,160
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22603186
Author URL: https://archiveofourown.org/users/BlissHellfire/pseuds/BlissHellfire
Summary: If tumblr, reddit and the Undertale fandom had a kid, this would be it.~Basically used tumblr/reddit posts as writing prompts. It didn't work out exactly how I wanted but it taught me alot about how to organize my writing when writing larger arcs with a bunch of disparate details.
Kudos: 5





	1. All Joking Aside

Mr Sans diligently writes out the quadratic formula, careful to explain the intricacies of exponents. Red finds his eye lights flickering in and out. He already knows all this crap.

(Why the fuck is the teacher so damn slow?)

While completing the last substitution, Mr Sans’s sweet voice continued to go on and on, sending Red deeper into his own head.

Previously, Red was situated in the back of the classroom until recently. Him, Nightmare, Killer and Dust would regularly crack the same jokes at Mr Sans’s expense. For Mr Sans’s part, he was none the wiser. However, after the marinara incident, Mr Sans’ patience for Nightmare's Gang had grown thin. He separated them to the far reaches of the classroom which left only Killer and Dust in the back. Killer and Dust, while trouble makers in the gang, only started shit cause of Nightmare.

Today felt like just any day to Red. Yeah, he was uncomfortable at first to be in the front but he got a nice view of Mr Sans’s ass so it was worth sacrificing some privacy.

The dry-erase marker slips out of Mr Sans’s hands, sending it to clatter across the floor. Mr Sans rolled his eyes.

“Oh, fuck me.”

“Maybe later.”

Before Red realizes what he said, Mr Sans breaks into full body laughter. It’s far louder than his normal chuckles. It snaps Red to the reality of the situation as it cascades out of his control. The other, much more studious, students gasp and break into laughter too.

THE ENTIRE CLASSROOM IS LAUGHING.

Red yanks up his hood but it doesn’t hide the gigantic crimson blush forming on his bones before Mr Sans’s sees it.

He stops laughing, smiles genuinely at him before turning his attention into bringing the classroom into some sort of order.

(Fuck! He saw)

Red buries his head deeper into his hoodie and smacks his head into the desk to hide any remainder of the day’s events. Despite, his arms being pressed over his ear holes, he can still hear Nightmare saying.

“Dusty? I think our Lil’ Red’s gotta a crush on Sansy. Why don’t you help him out?” Nightmare snickers along with the gang. “We can’t leave a him hanging.”

Red felt the magic flowing out from his soul. The magic seared his nerves as it traveled down his spine, through his pelvis and even heating up his feet from within his sneakers. Though, the worst of it traveled up his spine and more settled on his cheeks, making the blush worse. The heat made him want to strip down to his boxers. The mere idea made him get hotter at the idea of Sans smiling as he looked over him and licked his teeth with satisfaction at what he saw.

(What the fuck were you doing?! Now they know, they all know!)

Red wraps his arms tighter against his head until his magic reaches the breaking point. His left eye light engorges itself with all the excess magic. He’s gotta release it. He ain’t gonna last much longer like this. If he can just send it all out in one go.. and he knows who’s gonna take the full blast.

Without hesitation, Red leaps over his desk to alongside Mr Sans. Red turns to face Nightmare as he waves his hand to conjure his Gaster Blasters and fires. It was glorious to witness the 8-pronged octopus mess squirming to get away.

The blast went off.

Then all was white.

**Notes for the Chapter:**

> Most of the chapters are based on memes, tumblr and reddit posts so I'll do my best to cite them when there is an original source or a picture of the post. Enjoy :)
> 
> Edit 30 Nov 2020_ fixed end note links  
Tumblr/Reddit post that got this started. I only have a picture of the post so I just linked my archive blog [ Link](https://bh-reports.tumblr.com/post/632291189631139840/i-found-these-in-tumblrreddit-compilations-on)


	2. Thought of the Day

**Summary for the Chapter:**

> Thought of the Day is an old tradition at this high school. Let's just say, it doesn't go as planned...

During the morning announcement, Mr Sans steals a glance at the troubled student, Red. For once, he’s obediently listening in his seat rather than setting up his next joke or prank. Though, something seem off. Red’s smug as ever but hasn’t yet shared about what.

(He’s been oddly quiet this morning. Too quiet. I have to be on my guard for anything with this kiddo.)

Mr Sans listens back to the intercom as it finishes the lunch specials for this week. The student speaker switches the mic over to Principle Asgore.

“As for today’s thought of the day: a monster is not a monster until they kiss the lips that do not speak.”

The rough waters of the classroom and all rooms in the school go deadly quiet that you can hear a pin drop. A cacophony of gasps can be heard as realization dawns on the dirty minds of all thousand high schoolers of what just exactly had been said.

The current rushes in with the strength of a tsunami wave everyone erupts into laughter. Young and old. The quiet kid as well as the boisterous jock. Even the sleeping kid had woken up just for this moment.

The intercom comes back on. The students quiet down enough to hear a frazzled Asgore to say,

“I would like to report that we are no longer accepting anonymous submissions for thought of the day.”

Mr Sans couldn’t take it any more laughs. He can’t stifle it back thinking how flustered the big goat monster would he over this. He can bet that Undyne is doubling over in the gym. She’d definitely comment on this at the teacher’s lounge this afternoon to Asgore.

Asgore would never hear the end of it.

Over the roar of the classroom, he managed to stifle his laughter well from the average that none would he suspect. However, Red is no average student as Mr Sans realizes why Red had been so smug this morning. When Mr Sans accidently looks at Red, the grin is all the confirmation Mr Sans needed for his hypothesis.

(Red did this and I just gave him encouragement he needs for his negative attention-seeking behavior. Crud. Asgore, I’m never gonna hear the end of this either.)

“What do ya think, teach? This’s gotta be my favorite thought of the day yet. Don’t cha agree?”

“We’ve used enough class time.”

Mr Sans quickly dismisses him but he doubts he could dampen Red’s mood. Red looks like he’s about to burst from pride and his achievement.

(Shit! The kid got me good.)

“Class! Class?”

Mr Sans calls but the excitement of the morning’s drama had taken the classroom by storm. There is nothing Mr Sans can do to quell the rough waters except to wait until the tide of jubilation recedes.


	3. Three

**Notes for the Chapter:**

> All the square symbols are supposed to be the pi signs in math. I'll fix it at some point....

(The birds are singing. The rhodies are blooming. On days like these with kids like this, it’ll be far from a lethargic first period.)

Mr Sans waltzes into the classroom with a skip in his step. 

“Morning, kiddos. How’s your—” 

There’s already an equation on the whiteboard. 

‘ Notice me sin ‘

He can’t help but chuckle but instantly regrets it as he hears echoes from the rest of the classroom.

“Sin?” “Sin?” “Morning, Sin.” “Notice me, Sin!”

It feels as if a dense storm cloud descended over his classroom. As he wanted to crack up so badly, damn, if he didn’t have responsibilities as a teacher this would be hilarious. But if Alphys or Undyne came by…

At that inopportune moment, chances a glance back into the hall. He sees Undyne standing their with a huge wolfish grin plastered across her viage sending him finger guns. He knew before he heard the crack of Red’s laughter that EVERYONE in the teacher’s lounge would know EXACTLY what “notice me, senpai” means by lunch time. 

“Don’t.”

Undye smiles even wider. 

“Don’t know what you’re talkin’ about… sin.”

Which sends the ENTIRE classroom into ANOTHER bout of sin calls like a batch of seagulls.  
Mr Sans sighs, the damage has already been done. There’s no use crying over spilt milk, after all, regardless of how it looks now. His colleges would forget in a couple weeks.

On his way back to his desk, he pulls down the projector to find one of Red’s surprises, yet another math problem. This time, it’s in the form of a basic poster with a triangle labeled with a 90 degree angle as well as two arrows extending from it. One arrow points to the triangle declaring “acute” and the other points in the direction of himself. This one reads in big, bold and red letters --- “ACUTIE.”

He can’t help but feel the magic rush to his cheeks. His soul is already thinking about the teacher’s lounge, he can’t take another pun right now. He just needs to collect himself. He breaths and carefully pulls off the poster. He calmly put it onto a very satisfied Red’s desk. 

“Red, while I appreciate your hard work, I’ll need you to focus more on your studies. Also, this isn’t a right—”

“But I’m right about the other one, Sin.”

Mr Sans manages to pinch his nose before his blue blush spread too far over his face without him bringing it back under control. A couple pranks was one thing, this was distracting the class as well himself. 

Luckily, the rest of the lesson goes along uneventfully. Mr Sans even manages to get his first period caught up to the rest of his classes. Normally, once a class gets this far behind semester, they rarely catch up. It’s a satisfying feeling to bring this period back into the fold. Standardized testing would’ve been a nightmare otherwise. This way, they have the best chance to succeed and maybe even score enough to get into the college of their choosing. If only that was only obstacle…. He banishes such thoughts from his mind. He’s doing his best and so is the class, that’s the best he could ever hope for. 

Later in class, the kids get a head start on homework. That’s when Red approaches him with a sheepish grin. 

“Teach, can I get your help with somethin’? I dunno know how to simplify this.”  
Red slides an older assignment onto his desk.

“Red, I’d rather you work on today’s assignment.”

“Please. I…” He starts. “It’s just this one.”

9x + 7i < 3(3x + 7u)

Mr Sans sighs. “Sure. What do you remember about PEMDAS?”

“Parenthesis…” Red mumbles as he distributes the three. 

9x + 7i < 9x + 21u

“Subtraction?” Mr Sans nods.

7i < 21u

(You Little—)

He attempts to return the paper back but not before Red quickly writes.

I <3 u

Then he scrambles back to his desk gleefully. 

Mr Sans leans back in his seat. “How am I supposed to explain this to him?” He mutters.

(Three in a day? This is beginning to get ridiculous. It just…)

Mr Sans shivers at the thought as the memory touches the edge of his conscious mind, he quickly brushes it away. He didn’t have the time to think of That right now. 

He really just wishes Red would take the hint. He really needs another day to think it over. 

(Maybe I can talk to Asgore?.. no, he’d just suspend Red. We already know that doesn’t work.)

Mr Sans sighs. 

(No use thinkin’ now. There’s only a few minutes left of class. I can figure it out tonight.)

Mr Sans goes to pull up the projector to find— “How did even do this? I was…” He looks to Red and then back at the white board with a vertical line of toy pickup trucks filled slices of cheese. 

“You couldn’t have…” He looks back at Red who merely shrugs.

“Sorry for the cheesy pickup line, Sin. I know it’s not my best work.”

“Red! This isn’t a fucking drive through!” Mr Sans snaps back.

Red goes slack jaw for a couple moments before his eyelights turn into stars. 

(Fuck.)

(Helluva job, Sans. Now the kid’s starstruck!)

Before the class can start laughing, he waves, “class dismissed,” and promptly leaves.  
When he finally gets to a staff washroom, the embarrassment blush makes him look more akin to a blueberry than a skeleton. It was a good thing the staff washrooms are single use, otherwise…

(Dammit!) 

He was definitely going to set up a meeting with Red tomorrow. He’d settle this once and for all. 

(Stars, why did skeletons have to be prone to blushing more than other monsters?)

It nearly takes him until the start of second period for his cheeks to clear up. It finally dissipates as usual and slow as ever. On his way back to the classroom, Red pops out of a nearby classroom. 

(Great.)

“Hey, teach.” Red rubs the back of his neck as he walks in pace with Mr Sans. “Sorry, I didn’t mean to uh.. go over board like that.”

Mr Sans sighs, “just don’t do it again, okay?”

“Alright,” Red smiles back, “sorry, it’s just so hard to keep a straight face while lookin’ at ya.” He winks. 

At this, Mr Sans stops and his eye lights go out. “Meet me in my office. Tomorrow morning.”

“If ya wanted to meet me so soon, why not now?”

When Mr Sans final looks at him, Red shrinks back quicker than he could imagine possible. 

“S-s-sorry, Boss. I-i-i..urgh!” He puffs up his chest, “Okay! BE THAT WAY!” Then he sprints off.

**Notes for the Chapter:**

> Two Memes:  
\- Captain America in an elevator with Nazis (cheesy pickup line)  
\- Despicable Me, Gru and Vector (Sinpi)
> 
> The rest are tumblr posts but they seem like common pickup lines or jokes so I didn't cite them.


End file.
